Hi!
The airport is in northwest of the city. I think most of the expat pilots live in the surrounding of Saigon in some nice houses (which are quite cheap to rent) or in some appartments in the districts close to the airport. There are some who are living in city center district 1 or 3 which is a distance to the airport but manageable.
Housing costs are quite high in comparison to the costs of living there. You will find something reasonable.
I guess all the expats will go to work by taxi or taxi-moped.
The city is very busy and noisy. As all big asian cities. But I am sure you will get your sleep when you need it!!
Have you ever been to an asian city before?? Don't worry about the noise.